I'm turning my garden into raised beds. What soil should I use in the beds?...
You should begin by looking at our Vegetable website and 'Preparing the Soil'. Sources of organic matter include compost, well rotted manure, or leaf mold (composted leaves). Organic matter can be purchased in bulk. Leafgro (composted leaves) is a commercial yardwaste compost product available in bag and bulk throughout MD. http://extension.umd.edu/growit/food-gardening-101/step-3-prepare-your-soil
You can also call around to topsoil/mulch suppliers for commercially available mixtures of topsoil and leaf compost. This makes an excellent media for raised beds - blended topsoil (70%) and leaf compost (30%). Can be purchased by the cubic yard. You can use leafgro (see sources on the above site) and here is information on beginning your own home composting. hgic.umd.edu/content/documents/HG35BackyardComposting10_2010final_000.pdf
Whenever buying topsoil or organic matter in MD, it basically is 'buyer beware'. As far as compost, the only way to know exactly what you are putting in your veggie garden is to make it yourself.
See our videos on raised beds http://youtu.be/fB8W232p9-w,